[74.01] A Classical Gamma-Ray Burst Repeater?

R.E.Lingenfelter, V.Wang (UCSD)

We find that the sample of gamma-ray bursts, observed by the BATSE
experiment on the Compton Gamma Ray Observatory, has a conspicuous set
of 5 bursts which are closely associated in both space and time, separated
in position by less than their positional uncertainty and separated
in time by less than a few days. From a preliminary statistical analysis
of these associations, we estimate that the probability of such a set of
5 bursts being random is less than 10$^{-4}$, while the probability that
they come from a single repeating source is 85\%. Thus, we suggest that
these bursts arise from a repeating source at a location of $\sim$ 0855$-$00.
Unlike most of the ``soft" gamma-ray repeaters, these repeating bursts have
relatively hard spectra and widely varying durations, that are indistinguishable
from the common, ``classical" gamma-ray bursts.